Thread: Beth - New Build 'Boreal'

Andy,

Looks very good so far, I look forward to watching the progress.

Hi Andykane!

Fine models you made! Thank you for pictures!
Keep posting building photos here.
Feel free for asking of any problems in building - hoping to be able for answer of them.

I'll definitely keep posting photos. Hopefully soon thing will be looking more boat like.

I do have one question - the sheerclamps are mentioned in the plans and as far as I can tell they should be the same dimensions as the chine logs, but the sheerclamps don't seem to be listed in either the metric or imperial bill of materials. Is this a mistake or am I just not finding them there?

Originally Posted by Andykane

I do have one question - the sheerclamps are mentioned in the plans and as far as I can tell they should be the same dimensions as the chine logs, but the sheerclamps don't seem to be listed in either the metric or imperial bill of materials. Is this a mistake or am I just not finding them there?

Chine logs and sheerclamps 19/19 mm are.

Originally Posted by robhosailor

Chine logs and sheerclamps 19/19 mm are.

Perfect, because that's the size I cut them to!

To save time later I decided to cut most of the timber to size now, before I had a hull taking up space. I put a nice new blade on the bandsaw, adjusted the guides, aligned the fence, and everything went very smoothly. I use a "featherboard" to hold the wood firmly against the fence so I can just push or pull the wood through. Using this system I can cut perfect 5m long lengths by myself.

After cutting and then running them through the electric planer to final size, this is what I got:
Attachment 186017
Did the same for the spars, but haven't yet thicknessed them to final size. The 60mm diameter mast is a bit annoying to get out of 50mm thick stock but I decided that I'll glue up two 60x50 lengths and then cut the 60x60 mast out of the middle of the glued up section.

Attachment 186020
Next job was to cut out the bottom and sides, and to make the duplicate sides. I really like these japanese saws for cutting plywood because they cut very quickly, smoothly, and give you lots of control so you don't need to do much cleanup with a plane later.

Cutting out the bottom:


Attachment 186018
After cutting out the hull sides I planed them back to the line, traced the shape onto a second sheet of plywood, cut out the second side, and then clamped the two together and trimmed the copy to match the original. This method, given in the plans, seemed to work extremely well and apart from the pencil marks the copy and the original are indistinguishable.

Trimming copy:
Attachment 186019

Transferring bulkhead and knee lines across to copy:
Attachment 186021
After cutting all this wood I had to finally just move ahead and actually glue something.

Laying out the sheets to be glued:
Attachment 186022

First I coated the sheet with unthickened epoxy, then I coated the butt straps with thickened epoxy and clamped and nailed it all together. Next time I wouldn't thicken the epoxy quite a much but everything looks fine so far.

Attachment 186023

Attachment 186024
I have a lot of leftover "slow" (for high temperatures) epoxy hardener because I never seem to need it, and now that the temperatures are dropping I need to make sure the joints stay above 16°C. For this I just use a good old fashioned lightbulb under a draped sheet.

Attachment 186025


This is starting to feel like real progress; I can't wait to do more.

Originally Posted by Andykane

This is starting to feel like real progress; I can't wait to do more.

Looks great! Your progress is really quick.

More progress:

I cut out the bulkheads and then was trying to figure out where to locate the hatch holes in bulkheads 2, 3 and 4. To do that properly I needed to make the camber template. I marked out the points, roughly cut a curve to let me clamp a batten along the actual curve, then cut near the curve and used a spokeshave and sanding block to clean up the cut.



I decided to go with quarter turn locking circular hatches because they are cheap and effective. I'm going to go with 6" (150mm) hatches in bulkhead 2 and 4 and 2 x 8" (200mm) hatches in #3 bulkhead. These sizes are the opening size - the actual size needed in the bulkhead are about 8" for the smaller ones and about 10" for the larger ones. I thought about different options for hatches in the #3 bulkhead and decided that trying to make rectangular hatches would be too complicated and that buying rectangular ones would be too expensive (a rectangular hatch would be about $80 vs about $15 for the circular ones).

Drilling a hole and cutting the hatch opening with a keyhole saw worked fairly well but the saw was really a bit too coarse for this work and so there was some tearout. Getting into a rhythm of fast gentle strokes seemed to work better than more aggressive strokes but sometimes the saw bites in and you really can't help but take a big chomp out of the wood.


After initial cut:


To quickly and easily sand the inside of the hole I made a curved sanding block which worked really well. It has two sides - one to fit the larger holes and one for the smaller.



I also cut out all the knees, but for some reason I forgot to get a photo of them.

Finally, I masked off the bottom and the sides, but ran out of time before I could mask the bulkheads and knees.

I was happy to read that the bottom of the bottom and the outside of the sides don't need to be epoxy coated yet. This means I should be able to do everything in one go, which will save a lot of time.



It's a bit silly really, how many things in Canada (a metric country) are non-metric. I'm perfectly comfortable working in both systems but it seems weird to be fitting 8" hatches into bulkheads made from 6mm plywood and then have imperial sized drillbits, but metric widths of masking tape. But, as long as it all works out in the end then at least it keeps the brain active.

So I have a question for anyone who has done this epoxy coating: how do you get it smooth?

As soon as I coat my plywood thousands of tiny fibres lift up and form little points. Following the instructions and dragging a roller across them flattens them out, but they gradually spring up again so by the time the epoxy cures I end up with lots of little spikes.

I've scrubbed all the blush off and wetsanded the surface back to smooth (miserable work!) but I'm worried about coating future un-sandable areas like the underside of the decks.

I'm thinking that pre-sanding the plywood with some 220 grit paper might help smooth the surface and thus smooth the epoxy coat. Thoughts?

Originally Posted by Andykane

So I have a question for anyone who has done this epoxy coating: how do you get it smooth?

Sanding, sanding, sanding...

Epoxy coating made by me is not smooth!


maskingcoating06 by robhosailor, on Flickr


maskingcoating09 by robhosailor, on Flickr

***
My friend used a special thin polyester fabric (to cover the layer of epoxy resin), which was removed after curing epoxy resin. It happened correctly.

Originally Posted by Andykane

So I have a question for anyone who has done this epoxy coating: how do you get it smooth?

If it's not too late, I've gotten good results using a spreader rather than roller or brush. The technique is best for large flat areas, but can be used with smaller areas too. I did use a brush for the GIS's framing and chinelogs. The spreader I used was an inexpensive plastic spatula sold for drywall compound. It holds up well to multiple uses since the epoxy flakes off once hardened. Not only does it leave a decently smooth coat, the coat can be made really really thin which lowers the amount of epoxy used as well as how much the part weighs (probably not significant, but psychologically rewarding). I did sand between coats for those areas that will be exposed, but I'll admit that the buoyancy tank interiors are as rough as sandpaper.

Sounds like my experience is about normal. I've already finished all the inside surfaces including bulkheads and knees, and did do a whole lot of sanding.

I used a foam roller from West system for most of it but I do have some flexible plastic squeegees that I use for fiberglass and I did notice they left a nice smooth surface but I didn't think I could regulate the thickness well enough. Sounds like it might be worth another try.

More pictures soon!

Good work!

The plastic squeegees work well and, yes, you can control the thickness of the epoxy with them. I found the first coat used much more epoxy than the second - which used more than the third. All of which makes sense... the ply really soaks up that first coat.

I didn't experience the lifting of fibers when I coated my plywood. I applied three coats 'hot' - meaning I applied the next coat before the previous coat had cured. I didn't sand between coats (man, what a mess that would have been). Maybe I just didn't see that raised fiber effect - but it sounds pretty obvious from what you are describing.

Keep up the good work and, of course, post more photos!

Thanks for all the input on the epoxy coating. I'll definitely try using a squeegee instead of a roller next time.

Finally had a chance to make some more progress. I apologize for the quality of the photos - the cell phone camera is pretty pathetic in less than ideal conditions and my good camera was at home.

After coating everything with epoxy over 5 frantic and messy hours I came back to find the aforementioned rough mess. I got a bucket of hot water and a scouring pad (scotchbrite type pad) and washed off the amine blush. Despite working with epoxy on several other boats I've never really paid attention to this before since the epoxy has always just been used in joints - never as fillets or a coating. The waxy blush was easy to see because the water just beaded up on it. After some scrubbing the blush came off and the water smoothly covered the whole surface. I brought all the pieces outside and gave them a thorough wash with the hose and then left everything to dry.

In this photo you can see the texture left even after sanding. It feels a lot smoother than it looks so it'll be fine for the inside, but for the outside I'll need to get it smoother or it'll look pretty terrible when it's painted.



Next step was to fit and glue the chinelogs. I have several dozen plastic spring clamps left over from making a skin on frame canoe so I began by clamping the chinelog to the bottom at the widest point, working my way aft to the stern and then forward to the bow. With the first chine log clamped in position I could easily drill pilot holes and screw the logs into place with the temporary screws and pads.



I considered not using the screws and just using clamps to save time but I think without a helper it would be difficult to be sure everything was lined up properly. With the screws you might take slightly longer but it's easy to get the logs exactly in the right position.

With the first log in place I measured the required angle at the stern and cut the chine log to match. I moved forward, clamping as I went, until the log was in place for most of the length but resting on the other chine log where they crossed at the bow. I then measured the angle for that end and cut the end to match, trimming it very slightly with a block plane to get it to fit nicely.

After all this, it was time to break out the epoxy. I decided to do things properly, so I brushed unthickened epoxy onto the bottom and the chine log and then used the plastic bag with a corner cut off technique to put a bead of thickened epoxy on the bottom. This worked extremely well because with the bag I could easily regulate how much thickened epoxy I used. Wish I'd stopped to take a photo, but having to take off the gloves and worry about getting epoxy on the camera/cell phone is a bit of a hassle. I didn't bother to spread the thickened epoxy and this worked fine - the pressure from the screws was more than enough to get a good amount of epoxy squeezing out on both sides.

Another benefit to the screws over the clamps is that you know exactly where the chine log should be at the center before you have the ends installed. I could put a screw in at the middle and then work my way to the ends and everything lined up properly and went very smoothly. The bend at the stern is pretty sharp, but I still managed to do it while putting the screws in with my other hand.

All glued up. Since the top and outside are so easily accessible I'll just clean them up with a plane later rather than doing it all now while it's soft.


I also glued up the stem. Since it's so simple I just clamped it in place and that seemed to work fine.


Made sure to leave enough space for the chine logs and bottom.


And directly ignoring Michael's advice to not goop leftover epoxy on the boat, I filled the small gaps between the bottom stiffeners and the chine logs with epoxy to prevent dirt from collecting there. I figure the (very) small weight penalty will be worth it to make things easier to keep clean.


Finally, I've been keeping track of my hours and costs on the project, and if anyone's interested they can take a look at the spreadsheet here:
https://docs.google.com/spreadsheet/...=1&output=html

So far I my estimated times have been reasonable apart from the epoxy coating which, including masking and scrubbing and sanding, took 10 hours instead of the estimated 4.

Moving ahead, the next step is to notch the bulkheads to fit over the chinelogs and sheerclamps. First I decided to check how much needed to be trimmed off the bulkheads when... disaster! Bulkhead 2 was about 20mm too narrow. I worriedly checked the rest of the bulkheads but luckily they were all correct. Turns out I somehow measured the correct distance from centerline to one side, and then measured a totally different distance from the centerline to the other side. I do have enough plywood to make a new bulkhead but instead I decided to butt-join a small extension to the edge of the bulkhead. This should be more than strong enough, and since it's on the forward side of bulkhead #2 it will be essentially impossible to see once the boat is together.

Extension piece (6mm ply) and butt-strap (4mm ply)


Glued up


That problem solved I notched the rest of the bulkheads and got to attaching the hull sides.

Cleaned off the bottom


And started attaching the starboard side. I had a helper support the side while I lined up the stem and put the first screw in but the rest was easy enough by myself. I found that putting spacers under the hull bottom to bring it up to the final rocker curve made everything line up properly and made the process much easier.

Half way there...


The second side was pretty straightforward. Everything seemed to just fit into place:



I slipped the 3 finished bulkheads into place, and she looks like a boat!




Next I need to take all those screws out and actually glue all of this.